Scientists looked at personality traits and rate of dementia in older people

People who have a cynical distrust of others, and think their motives are selfish, could have a higher risk of developing dementia, a study has said.

Researchers compared levels of cynical distrust in 622 people with the incidence of dementia.

They said people with high levels of distrust were twice as likely to develop dementia.

Experts said any findings that helped understand the disease were important, but called for larger studies.

Personality and disease

Dementia is a syndrome categorised by a decline in memory, thinking speed, mental agility, language, understanding and judgement.

One in three people aged over 65 in Britain will develop dementia, according to the Alzheimer’s Society in the UK.

In 1998, volunteers, with an average age of 71, were asked to rate their agreement with statements such as “I think people would lie to get ahead”, or “it is safer to trust nobody”, said the researchers.

Scientists at the University of Eastern Finland said 46 people had developed dementia in the following decade.

Fourteen of the 164 people who showed high levels of cynical distrust in 1998 had developed dementia in this time, compared with nine out of the 212 people with low levels.

Dr Anna-Maija Tolppanen at the University of Eastern Finland led the study.

She said: “These results add to the evidence that people’s view on life and personality may have an impact on their health.”

Explaining the results, Dr Tolppanen said: “People with different personality traits may be more or less likely to engage in activities that are beneficial for cognition, such as healthy diet, cognitive or social activities, or exercise.

“Or personality may act via morphological changes or structural differences in brains. Also, inflammation has been suggested as one link between cynicism and worse health outcomes.”

She said the study was controlled for socioeconomic factors, age, sex, health status, and lifestyle, such as smoking and alcohol use.

Role of depression

But Dr Tolppanen said she had not accounted for people becoming depressed after the first stage of the assessment, or that the volunteers’ depression might not have showed up adequately in questionnaires.

She added it was “really important” to replicate the findings on a much larger scale, to prove the link.

Dr Simon Ridley, head of research at Alzheimer’s Research UK, said: “With the rising numbers of people affected with dementia, any addition our understanding of what might affect disease development is important.”

He said that as only a small number of people in the study developed dementia, he would want to see a larger study conducted to be “more confident” in the proposed link.

Dr Ridley said the volunteers with a high level of cynical distrust could have been already beginning to develop dementia, and that depression, which may be both a risk factor and a symptom for dementia, could account for the cynicism.

Browning meat in the oven, grill or frying pan produces chemicals which may increase the risk of developing dementia, US researchers suggest.

Advanced glycation end (AGE) products have been linked to diseases such as type-2 diabetes.

Mice fed a high-AGEs diet had a build-up of dangerous proteins in the brain and impaired cognitive function.

Experts said the results were “compelling” but did not provide “definitive answers”.

AGEs are formed when proteins or fats react with sugar. This can happen naturally and during the cooking process.

Researchers at the Icahn school of medicine at Mount Sinai, in New York, tested the effect of AGEs on mice and people.

The animal experiments, published in Proceedings of the National Academy of Sciences, showed that a diet rich in AGEs affects the chemistry of the brain.

It leads to a build-up of defective beta amyloid protein – a hallmark of Alzheimer’s disease. The mice eating a low-AGEs diet were able to prevent the production of damaged amyloid.

The mice performed less well in physical and thinking tasks after their AGEs-rich diet.

A short-term analysis of people over 60 suggested a link between high levels of AGEs in the blood and cognitive decline.

‘Effective treatment’

The study concluded: “We report that age-related dementia may be causally linked to high levels of food advanced glycation end products.

“Importantly, reduction of food-derived AGEs is feasible and may provide an effective treatment strategy.”

Derek Hill, a professor of medical imaging sciences at University College London, commented: “The results are compelling.

“Because cures for Alzheimer’s disease remain a distant hope, efforts to prevent it are extremely important, but this study should be seen as encouraging further work, rather than as providing definitive answers.

“But it is grounds for optimism – this paper adds to the body of evidence suggesting that using preventative strategies might reduce the prevalence of Alzheimer’s disease and other dementias in society and that could have very positive impact on us all.”

Dr Simon Ridley, from the charity Alzheimer’s Research UK, said: “Diabetes has previously been linked to an increased risk of dementia, and this small study provides some new insight into some of the possible molecular processes that may link the two conditions.

“It’s important to note that the people in this study did not have dementia. This subject has so far not been well studied in people, and we don’t yet know whether the amount of AGEs in our diet might affect our risk of dementia.”

Exercise throughout a person’s life plays a significant role in reducing the risk of developing dementia, a study spanning 35 years has found.

The Cardiff University study which began with 2,235 men from Caerphilly in 1979 found factors including diet and not smoking had an impact on preventing illnesses developing in older age.

However exercise had the single biggest influence on dementia levels.

This week a G8 summit will hear dementia will affect 135m by 2050.

‘Really amazed us’

The research by Cardiff University found the five factors that were integral to helping avoid disease were regular exercise, not smoking, low bodyweight, healthy diet and low alcohol intake.

Caerphilly Cohort Study

The study has followed a group of 2,235 men aged between 25 and 49 from Caerphilly, just north of Cardiff, since 1979.

It has recorded their behaviour in relation to their health over that period, initially focusing on the causes of heart disease, which was particularly high in the area.

As time has gone on, the study has moved to looking at the effects of dementia and strokes.

Over 400 research papers in the medical press have been produced from its findings.

One of the contributions was the discovery that aspirin helped prevent heart attacks.

The study has been funded by the Medical Research Council, the Alzheimer’s Society and the British Heart Foundation.

People in the study who followed four of these had a 60% decline in dementia and cognitive decline rates, with exercise named as the strongest mitigating factor.

They also had 70% fewer instances of diabetes, heart disease and stroke, compared with people who followed none of the factors.

Professor Peter Elwood, who led the study on behalf of Cardiff School of Medicine, said healthy behaviour was far more beneficial than any medical treatment or preventative procedure.

“The size of reduction in the instance of disease owing to these simple healthy steps has really amazed us and is of enormous importance in an ageing population,” he said.

“Taking up and following a healthy lifestyle is however the responsibility of the individual him or herself.

“Sadly, the evidence from this study shows that very few people follow a fully healthy lifestyle.”

‘More active lifestyle’

Prof Elwood stressed that while one aspect of the five strands of behaviour mentioned may have more impact on certain illnesses, the emphasis was on an overall healthy lifestyle.

“Exercise happens to be the most important but the other factors come in very close behind,” he added.

He told BBC Wales while the recommended levels of exercise were half an hour five times a week, it did not mean having to go to a gym.

“We should all live a more active lifestyle. If I park my car a mile from work – that makes me likely to do more than the half an hour a day. Any exercise has some benefit and the more, the better.”

The research showed that while smoking levels had dropped over the 35 years, the number of people leading what the team described as a fully healthy lifestyle had not changed.

“

This study provides more evidence to show that healthy living could significantly reduce the chances of developing dementia”

Dr Doug BrownAlzheimer’s Society

These findings are replicated across Wales, according to recent surveys, which showed less than 1% of the population have a fully healthy lifestyle, with 5% not following any of the five recommended points.

Prof Elwood added: “If the men had been urged to adopt just one additional healthy behaviour at the start of the study 35 years ago, and if only half of them complied, then during the ensuing 35 years there would have been a 13% reduction in dementia, a 12% drop in diabetes, 6% less vascular disease and a 5% reduction in deaths.”

Prof Elwood said everyone had to take personal responsibility for their health

Dr Doug Brown from the Alzheimer’s Society said: “‘We have known for some time that what is good for your heart is also good for your head, and this study provides more evidence to show that healthy living could significantly reduce the chances of developing dementia.

‘These large, longitudinal studies are expensive and complicated to run, but are essential to understand how dementia can be prevented.”

The research team estimated that unhealthy living has accounted for around 10% of the NHS budget in Wales since the study began.

Health Minister Mark Drakeford said the study “threw into sharp relief” the extent to which preventing illness lay in a person’s own hands.

Dr Simon Ridley, of Alzheimer’s Research UK, said that from this study, it was hard to know whether stress contributed directly to the development of dementia, whether it was purely an indicator of another underlying risk factor in this population of women, or whether the link was due to an entirely different factor.

“We know that the risk factors for dementia are complex and our age, genetics and environment may all play a role. Current evidence suggests the best ways to reduce the risk of dementia are to eat a balanced diet, take regular exercise, not smoke, and keep blood pressure and cholesterol in check.

“If you are feeling stressed or concerned about your health in general, we would recommend you talk this through with your GP.”